The present invention concerns the synthesis and placement of polymers at known locations on a substrate. The collection of all the polymers on a substrate is known as an array. The methods described may be applied, for example, to create solid-phase sources of chemical diversity, such as arrays of peptides, oligosaccharides, polymeric nucleic acid, etc., on a substrate, for use in screening for biological activity.
The preferred means for preparing arrays employs radiation-labile protecting groups and photolithographic masks to achieve spatially defined combinatorial polymer synthesis on a substrate surface. One preferred prior technique is shown in U.S. Pat. No. 5,143,854, which is incorporated by reference in its entirety for all purposes. Using photolithographic techniques for preparing solid-phase polymer arrays have met with considerable success. Nonetheless, it is desirable to meet a level of 100% efficiency. It would be beneficial therefore, to develop faster methods with greater yields (with minimal or no highly reactive byproducts) to make the current photochemical polymer synthetic processes more efficient and economical.